* Failover (2 sites are avail) + Backup & Restore
All support replication. NetApp has SnapVault, while EMC has RecoverPoint. RecoverPoint is simply the best replication technology on the market at the moment. It's journal based, so you can roll back to any point in time. Other technologies allow you to roll back to a snapshot or just the current image.

* Automatic Failover without any human or maschine interaction?
Cross-site? No - nor would you want it to be automatic. Things like VMware SRM goes a long way to automating the process, though. EMC's VPLEX will let you build a VMware environment across two separate DCs and so automate movement of VMs (or cluster nodes) across two DCs up to about 100km apart

* Performance
Depends on the array configuration. Add enough SSD drives and any of them will go like stink.

* Usability
Each vendor reckons their UI is awesome. EMC and NetApp have vCenter Server plug-ins that allow you to manage your array from vCenter Server. Which is nice. I don't know if Lefthand has the same.

* Scalability
NetApp and EMC go up to 144 and 125 drives respectively. HP say 230GB for the Lefthand box.

* Disaster Recovery
You can use any of the boxes as a starting point for a DR strategy, but that is a much, mcuh bigger conversation than the hardware. It's about business and IT processes.

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Veeam is happy to provide a free NFR license (1 year, 2 sockets) to all certified IT Pros. The license allows for the non-production use of Veeam Availability Suite v9.5 in your home lab, without any feature limitations. It works for both VMware and Hyper-V environments